CN114534741B - Attapulgite/manganese dioxide/ferroferric oxide nanocomposite and preparation method and application thereof - Google Patents
Attapulgite/manganese dioxide/ferroferric oxide nanocomposite and preparation method and application thereof Download PDFInfo
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- CN114534741B CN114534741B CN202210069328.3A CN202210069328A CN114534741B CN 114534741 B CN114534741 B CN 114534741B CN 202210069328 A CN202210069328 A CN 202210069328A CN 114534741 B CN114534741 B CN 114534741B
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- manganese dioxide
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- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 title claims abstract description 90
- 229910052625 palygorskite Inorganic materials 0.000 title claims abstract description 70
- 229960000892 attapulgite Drugs 0.000 title claims abstract description 67
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 title claims abstract description 54
- 239000002114 nanocomposite Substances 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- 239000002957 persistent organic pollutant Substances 0.000 claims abstract description 14
- 239000002245 particle Substances 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 26
- 238000010438 heat treatment Methods 0.000 claims description 20
- 239000000843 powder Substances 0.000 claims description 19
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 238000001035 drying Methods 0.000 claims description 15
- 239000002244 precipitate Substances 0.000 claims description 13
- 238000003756 stirring Methods 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 12
- WAEMQWOKJMHJLA-UHFFFAOYSA-N Manganese(2+) Chemical compound [Mn+2] WAEMQWOKJMHJLA-UHFFFAOYSA-N 0.000 claims description 9
- 239000003638 chemical reducing agent Substances 0.000 claims description 9
- 229910001437 manganese ion Inorganic materials 0.000 claims description 9
- 239000012286 potassium permanganate Substances 0.000 claims description 9
- 238000000227 grinding Methods 0.000 claims description 8
- 230000000593 degrading effect Effects 0.000 claims description 7
- SURQXAFEQWPFPV-UHFFFAOYSA-L iron(2+) sulfate heptahydrate Chemical compound O.O.O.O.O.O.O.[Fe+2].[O-]S([O-])(=O)=O SURQXAFEQWPFPV-UHFFFAOYSA-L 0.000 claims description 7
- 238000001816 cooling Methods 0.000 claims description 5
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims description 5
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 5
- 238000005303 weighing Methods 0.000 claims description 5
- 238000009210 therapy by ultrasound Methods 0.000 claims description 4
- 229910021380 Manganese Chloride Inorganic materials 0.000 claims description 3
- GLFNIEUTAYBVOC-UHFFFAOYSA-L Manganese chloride Chemical compound Cl[Mn]Cl GLFNIEUTAYBVOC-UHFFFAOYSA-L 0.000 claims description 3
- 239000011565 manganese chloride Substances 0.000 claims description 3
- 235000002867 manganese chloride Nutrition 0.000 claims description 3
- 229940099607 manganese chloride Drugs 0.000 claims description 3
- 229940099596 manganese sulfate Drugs 0.000 claims description 3
- 239000011702 manganese sulphate Substances 0.000 claims description 3
- 235000007079 manganese sulphate Nutrition 0.000 claims description 3
- 239000002105 nanoparticle Substances 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 2
- 238000004140 cleaning Methods 0.000 claims 1
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical group [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 claims 1
- 230000003197 catalytic effect Effects 0.000 abstract description 14
- 239000000463 material Substances 0.000 abstract description 14
- 238000011084 recovery Methods 0.000 abstract description 6
- 238000004064 recycling Methods 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 5
- 238000005054 agglomeration Methods 0.000 abstract description 4
- 230000002776 aggregation Effects 0.000 abstract description 4
- YYYARFHFWYKNLF-UHFFFAOYSA-N 4-[(2,4-dimethylphenyl)diazenyl]-3-hydroxynaphthalene-2,7-disulfonic acid Chemical compound CC1=CC(C)=CC=C1N=NC1=C(O)C(S(O)(=O)=O)=CC2=CC(S(O)(=O)=O)=CC=C12 YYYARFHFWYKNLF-UHFFFAOYSA-N 0.000 description 28
- 239000002351 wastewater Substances 0.000 description 25
- STZCRXQWRGQSJD-GEEYTBSJSA-M methyl orange Chemical compound [Na+].C1=CC(N(C)C)=CC=C1\N=N\C1=CC=C(S([O-])(=O)=O)C=C1 STZCRXQWRGQSJD-GEEYTBSJSA-M 0.000 description 19
- 229940012189 methyl orange Drugs 0.000 description 19
- 230000015556 catabolic process Effects 0.000 description 18
- 238000006731 degradation reaction Methods 0.000 description 18
- IQFVPQOLBLOTPF-HKXUKFGYSA-L congo red Chemical compound [Na+].[Na+].C1=CC=CC2=C(N)C(/N=N/C3=CC=C(C=C3)C3=CC=C(C=C3)/N=N/C3=C(C4=CC=CC=C4C(=C3)S([O-])(=O)=O)N)=CC(S([O-])(=O)=O)=C21 IQFVPQOLBLOTPF-HKXUKFGYSA-L 0.000 description 16
- 235000012730 carminic acid Nutrition 0.000 description 15
- 239000003054 catalyst Substances 0.000 description 14
- 239000001048 orange dye Substances 0.000 description 14
- 238000004042 decolorization Methods 0.000 description 12
- 239000000975 dye Substances 0.000 description 10
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 9
- 239000002131 composite material Substances 0.000 description 8
- ISPYRSDWRDQNSW-UHFFFAOYSA-L manganese(II) sulfate monohydrate Chemical group O.[Mn+2].[O-]S([O-])(=O)=O ISPYRSDWRDQNSW-UHFFFAOYSA-L 0.000 description 8
- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 description 7
- 229940043267 rhodamine b Drugs 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000001914 filtration Methods 0.000 description 5
- 238000001027 hydrothermal synthesis Methods 0.000 description 5
- -1 papermaking Substances 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000000706 filtrate Substances 0.000 description 4
- 239000012528 membrane Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 238000002798 spectrophotometry method Methods 0.000 description 4
- 230000003213 activating effect Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910044991 metal oxide Inorganic materials 0.000 description 3
- 150000004706 metal oxides Chemical class 0.000 description 3
- JRKICGRDRMAZLK-UHFFFAOYSA-L peroxydisulfate Chemical compound [O-]S(=O)(=O)OOS([O-])(=O)=O JRKICGRDRMAZLK-UHFFFAOYSA-L 0.000 description 3
- 238000007789 sealing Methods 0.000 description 3
- 229910003321 CoFe Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 239000010919 dye waste Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 229910052723 transition metal Inorganic materials 0.000 description 2
- 150000003624 transition metals Chemical class 0.000 description 2
- RBTBFTRPCNLSDE-UHFFFAOYSA-N 3,7-bis(dimethylamino)phenothiazin-5-ium Chemical compound C1=CC(N(C)C)=CC2=[S+]C3=CC(N(C)C)=CC=C3N=C21 RBTBFTRPCNLSDE-UHFFFAOYSA-N 0.000 description 1
- 229910020599 Co 3 O 4 Inorganic materials 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 229910000323 aluminium silicate Inorganic materials 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 229940088710 antibiotic agent Drugs 0.000 description 1
- 239000000987 azo dye Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- JZGWEIPJUAIDHM-UHFFFAOYSA-N chembl2007771 Chemical compound C1=CC=C2C(N=NC3=C4C(=CC(=CC4=CC=C3O)S(O)(=O)=O)S(O)(=O)=O)=CC=C(S(O)(=O)=O)C2=C1 JZGWEIPJUAIDHM-UHFFFAOYSA-N 0.000 description 1
- 239000002734 clay mineral Substances 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 238000000635 electron micrograph Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 239000010985 leather Substances 0.000 description 1
- 244000144972 livestock Species 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000007885 magnetic separation Methods 0.000 description 1
- 239000011572 manganese Substances 0.000 description 1
- CNFDGXZLMLFIJV-UHFFFAOYSA-L manganese(II) chloride tetrahydrate Chemical compound O.O.O.O.[Cl-].[Cl-].[Mn+2] CNFDGXZLMLFIJV-UHFFFAOYSA-L 0.000 description 1
- 229960000907 methylthioninium chloride Drugs 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000011943 nanocatalyst Substances 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 239000002073 nanorod Substances 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001699 photocatalysis Effects 0.000 description 1
- 230000029553 photosynthesis Effects 0.000 description 1
- 238000010672 photosynthesis Methods 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 229910000314 transition metal oxide Inorganic materials 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
- 238000003911 water pollution Methods 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/889—Manganese, technetium or rhenium
- B01J23/8892—Manganese
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
- B01J35/33—Electric or magnetic properties
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/10—Heat treatment in the presence of water, e.g. steam
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
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- Life Sciences & Earth Sciences (AREA)
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- Catalysts (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention discloses an attapulgite/manganese dioxide/ferroferric oxide nanocomposite and a preparation method and application thereof. The natural attapulgite which is cheap and easy to obtain is used as a carrier of the nano composite material, and can prevent the agglomeration of manganese dioxide particles, thereby improving the catalytic activity. The addition of the ferroferric oxide particles allows the nanocomposite to be rapidly separated from the solution by a magnetic recovery technique that is simple to operate. The prepared nanocomposite has the advantages of high catalytic efficiency, wide pH application range, easy recovery, recycling, simple preparation process, low cost and the like, and has wide application prospect in the aspect of treating organic pollutants.
Description
Technical Field
The invention relates to the technical field of nano materials, in particular to an attapulgite/manganese dioxide/ferroferric oxide nano composite material, a preparation method thereof and application thereof in degrading organic pollutants.
Background
With the vigorous development of industries such as textile, papermaking, leather, medical treatment, livestock and the like, a large amount of organic pollutants are generated, so that the water pollution is more serious. The organic wastewater contains a large amount of organic pollutants (such as methylene blue, methyl orange, acid scarlet, phenol, antibiotics and the like), has the characteristics of large chromaticity, strong biotoxicity, difficult degradation and the like, influences the photosynthesis of aquatic plants, and seriously endangers the ecological environment and human health. Therefore, the treatment of organic wastewater has become an urgent water environment problem to be solved.
In recent years, advanced oxidation technologies (such as Fenton or Fenton-like technologies, photocatalytic oxidation, and the like) have been attracting more and more attention due to their excellent degradation performance on organic pollutants. With conventional oxidizing agent H 2 O 2 Compared with the Fenton-like reaction in which the Persulfate (PMS) or the Persulfate (PS) participates, the target pollutant can be oxidized more thoroughly, and the applicable pH range is wide. Among them, PMS is activated by various methods such as heating, ultraviolet irradiation, transition metal oxide, etc. Currently, transition metal catalysts, e.g. CuO, ceO 2 、Fe 2 O 3 、Co 3 O 4 And MnO 2 As a PMS catalyst, attention has been paid to its advantages such as low energy consumption, low cost, good reactivity, and the like. Among these transition metal catalysts, manganese dioxide has higher cost performance, better catalytic activity and lower toxicity, and is one of the catalysts most suitable for practical application. Wu Guangrui (2018) and the like 2 For activating PMS degradation rhodamine B, 91% rhodamine B degradation was obtained within 20 minutes. Luo Moufu (2015) on fibrous catalyst alpha-MnO 2 The PMS heterogeneous catalytic degradation system research shows that the degradation efficiency of phenol reaches 100% within 10 minutes. However, manganese dioxide nanoparticles are susceptible to agglomeration, resulting in a significant decrease in specific surface area, available active sites and catalytic activity. In order to maintain excellent catalytic activity of manganese dioxide, manganese dioxide needs to be supported on a stable carrier.
The natural attapulgite (also called palygorskite) is a nano rod-shaped clay mineral (crystal diameter 40 nm) of chain layered magnesium-containing aluminosilicate, and has the characteristics of unique rod-shaped crystal structure, large specific surface area, developed nano holes and the like. It is reported that attapulgite having excellent dispersibility can prevent agglomeration of manganese dioxide particles as a low-cost, environment-friendly catalyst or catalyst carrier.Li et al (2013) prepared an attapulgite-loaded Ce 1-x Mn x O 2 The catalytic degradation rate of the mesogenic oxide to methyl orange can reach 98 percent. However, the disadvantages of difficult recovery, difficult separation, etc. limit the practical engineering applications of nanocatalysts. Many studies have demonstrated that the magnetic material ferroferric oxide can solve these problems. In addition, ferroferric oxide is widely used as an adsorbent or a catalyst for removing organic pollutants, heavy metals, dyes, etc.
Therefore, the invention takes the attapulgite as the raw material, and potassium permanganate, a divalent manganese ion reducing agent and ferroferric oxide are added, and the attapulgite/manganese dioxide/ferroferric oxide nanocomposite is prepared by a hydrothermal method. Solves the problem of poor effect of catalyzing and degrading organic pollutants by using single attapulgite or metal oxide, and provides a new material and a new method for treating the organic pollutants.
Disclosure of Invention
The invention aims to solve the technical problems of poor effect and difficult recovery of organic pollutant catalytic degradation by using a single attapulgite or metal oxide.
In order to solve the problems existing in the above technology, the technical solution of the present invention is:
the preparation method of the attapulgite/manganese dioxide/ferroferric oxide nano composite material comprises the following steps: (1) Weighing a certain amount of ferrous sulfate heptahydrate, dissolving the ferrous sulfate heptahydrate in water, adding polyvinylpyrrolidone, stirring and heating, adding a sodium hydroxide solution with the concentration of 3-5 mol/L into the solution, continuously heating and stirring after the solution generates blue-green precipitate, stopping heating and cooling to room temperature after the blue-green precipitate turns black, centrifuging, washing and drying to obtain ferroferric oxide powder;
(2) The attapulgite is used as a raw material, potassium permanganate, a divalent manganese ion reducing agent and the ferroferric oxide powder obtained in the step (1) are added, pure water is added, the mixture is oscillated in a water bath oscillator, the mixture is subjected to ultrasonic treatment, centrifugation, washing and drying, and grinding is carried out until the granularity is above 200 meshes, thus obtaining the attapulgite/manganese dioxide/ferroferric oxide nanocomposite.
Further, in the step (1), the heating temperature is 70 to 80 ℃, and the duration of heating and stirring is 1.5 to 2 h.
Further, in the step (2), the potassium permanganate amount is 40 to 60% of the mass of the attapulgite.
Further, in the step (2), the amount of the divalent manganese ion reducing agent is 0.0319 to 0.0390mol/L.
Further, in the step (2), the mass ratio of the ferroferric oxide powder to the attapulgite is 1:3.3 to 1:5.
further, in step (2), the conditions of water bath and drying are: oscillating 5-6 h in a water bath oscillator at 20-25 ℃ and 200-250 rpm, washing and centrifuging the obtained product, and drying 12-24 h in an oven at 50-60 ℃.
Further, in the step (2), the attapulgite is attapulgite powder, and the particle size is 200-320 meshes, namely 75-45 μm.
Further, in the step (2), the divalent manganese ion reducing agent is manganese sulfate or manganese chloride.
An attapulgite/manganese dioxide/ferroferric oxide nanocomposite material, wherein the attapulgite has a nano rod-shaped structure, and ferroferric oxide nano particles and manganese dioxide particles are attached to the surface of the attapulgite.
Further, the application of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite in degrading organic wastewater.
Compared with the prior art, the invention has the following beneficial effects:
1. the attapulgite is used as a carrier of the nanocomposite material, can prevent manganese dioxide particles from agglomerating, ensures that the manganese dioxide has better dispersibility and larger specific surface area, and has more active sites on the surface of the material, thereby improving the catalytic activity. The addition of the ferroferric oxide particles allows the nanocomposite to be rapidly separated from the solution by a magnetic recovery technique that is simple to operate. And secondly, the ferroferric oxide can also be used as a catalyst promoter of manganese dioxide, so that the catalytic performance of the ferroferric oxide is improved.
2. The attapulgite/manganese dioxide/ferroferric oxide nanocomposite is prepared by a hydrothermal method, and the problem of poor effect of catalyzing and degrading organic pollutants by using single attapulgite or metal oxide is solved.
3. The attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared by a hydrothermal method has the advantages of high degradation efficiency on organic pollutants, wide pH application range, easy recovery, recycling, simple preparation process, low cost and the like, and has wide application prospect in the aspect of treating organic wastewater.
Drawings
FIGS. 1 (a) and (b) are SEM photographs of attapulgite and an attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared according to the present invention, respectively.
FIG. 2 is a graph showing the decolorization rate of an attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared according to the present invention on acid scarlet (GR), carmine, congo red, and methyl orange dye wastewater.
FIG. 3 is a graph showing the degradation efficiency of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared by the invention with respect to phenol.
FIG. 4 shows the recycling decolorization efficiency of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared by the invention on acid scarlet (GR) dye wastewater.
Detailed Description
The invention will be described in further detail with reference to the drawings and the specific examples.
Example 1
(1) Weighing 0.278 g ferrous sulfate heptahydrate, dissolving in 100 mL water, adding 1 g polyethylene pyrrolidone (PVP) into the solution, stirring and heating to 80 ℃, adding 3 mol/L sodium hydroxide solution into the solution, continuously heating and stirring for 2 h after the solution generates blue-green precipitate, stopping heating and cooling until the precipitate in the solution turns black, centrifuging to obtain lower precipitate, washing and drying to obtain ferroferric oxide powder, and sealing for standby.
(2) Adding 3 g attapulgite powder into a 150 mL grinding conical flask, adding 1.5 g potassium permanganate, 0.6 g manganese sulfate monohydrate (in the embodiment, the divalent manganese ion reducing agent is manganese sulfate, particularly manganese sulfate monohydrate, of course, the divalent manganese ion reducing agent can also be manganese chloride, particularly manganese chloride tetrahydrate) and 0.8 g ferroferric oxide powder obtained in the step (1), adding 100 mL pure water, oscillating 5 h in a water bath oscillator at 20 ℃ and 200 rpm, carrying out ultrasonic treatment, centrifuging and washing, drying the obtained product in an oven at 60 ℃ for 12 h, and grinding to more than 200 meshes to obtain the attapulgite/manganese dioxide/ferroferric oxide nanocomposite.
Respectively selecting acid scarlet (GR), carmine, congo red and methyl orange dye wastewater of 200 mg/L and 50 mL respectively, adding the acid scarlet (GR), carmine, congo red and methyl orange dye wastewater into a centrifuge tube of 100 mL, adding a PMS solution with the concentration of 2 mL of 30 mmol/L into the centrifuge tube, adjusting the pH value of the solution to be=5, adding the nanocomposite of the invention to 0.05 g, oscillating the mixture in a constant-temperature water bath oscillator at 25 ℃ and 250 rpm for 6 h, sampling the mixture at a preset time, and measuring the concentration of the acid scarlet (GR), carmine, congo red and methyl orange dye wastewater by spectrophotometry on the filtrate after filtering the 0.45 mu m microporous filter membrane after precipitation. The nanocomposite of example 1 had 100%, 99.67%, 92.99%, 95.45% decolorization of acid scarlet (GR), carmine, congo red, methyl orange dye wastewater, respectively.
In addition, the preferable proportioning scheme is that the dosage of potassium permanganate is 40-60% of the weight of the attapulgite, the dosage of manganese sulfate monohydrate is 18-22% of the weight of the attapulgite, and the dosage concentration of manganese sulfate monohydrate is 0.0319-0.0390 mol/L.
Example 2
(1) Weighing 0.278 g ferrous sulfate heptahydrate, dissolving in 100 mL water, adding 1 g polyethylene pyrrolidone (PVP) into the solution, stirring and heating to 70 ℃, adding 4 mol/L sodium hydroxide solution into the solution, continuously heating and stirring for 2 h after the solution generates blue-green precipitate, stopping heating and cooling until the precipitate in the solution turns black, centrifuging to obtain lower precipitate, washing and drying to obtain ferroferric oxide powder. Sealing and storing for standby.
(2) Adding 3 g attapulgite powder into a 150 mL grinding conical flask, adding 1.2 g potassium permanganate, 0.54 g manganese sulfate monohydrate and 0.6 g ferroferric oxide powder obtained in the step (1), adding 100 mL pure water, oscillating 6 h in a water bath oscillator at 20 ℃ and 200 rpm, centrifuging, washing, drying the obtained product in an oven at 50 ℃ for 12 h, and grinding to more than 200 meshes to obtain the attapulgite/manganese dioxide/ferroferric oxide nanocomposite. Respectively selecting acid scarlet (GR), carmine, congo red and methyl orange dye wastewater of 200 mg/L and 50 mL respectively, adding the acid scarlet (GR), carmine, congo red and methyl orange dye wastewater into a centrifuge tube of 100 mL, adding a PMS solution with the concentration of 2 mL of 30 mmol/L into the centrifuge tube, adjusting the pH value of the solution to be=5, adding the nanocomposite of the invention to 0.05 g, oscillating the mixture in a constant-temperature water bath oscillator at 25 ℃ and 250 rpm for 6 h, sampling the mixture at a preset time, and measuring the concentration of the acid scarlet (GR), carmine, congo red and methyl orange dye wastewater by spectrophotometry on the filtrate after filtering the 0.45 mu m microporous filter membrane after precipitation. The decolorization ratio of the nanocomposite of example 2 to acid scarlet (GR), carmine, congo red, methyl orange dye wastewater was 99.59%, 99.16%, 92.41%, 96.15%, respectively.
Example 3
(1) Weighing 0.278 g ferrous sulfate heptahydrate, dissolving in 100 mL water, adding 1 g polyethylene pyrrolidone (PVP) into the solution, stirring and heating to 80 ℃, adding 5 mol/L sodium hydroxide solution into the solution, continuously heating and stirring for 2 h after the solution generates blue-green precipitate, stopping heating and cooling until the precipitate in the solution turns black, centrifuging to obtain lower precipitate, washing and drying to obtain ferroferric oxide powder. Sealing and storing for standby.
(2) Adding 3 g attapulgite powder into a 150 mL grinding conical flask, adding 1.8 g potassium permanganate, 0.66 g manganese sulfate monohydrate and 0.9 g ferroferric oxide powder obtained in the step (1), adding 100 mL pure water, oscillating 5 h in a water bath oscillator at 20 ℃ and 200 rpm, centrifuging, washing, drying the obtained product in an oven at 60 ℃ for 24 h, and grinding to more than 200 meshes to obtain the attapulgite/manganese dioxide/ferroferric oxide composite material.
Respectively selecting acid scarlet (GR), carmine, congo red and methyl orange dye wastewater of 200 mg/L and 50 mL respectively, adding PMS solution with concentration of 2 mL of 30 mmol/L into the solution, adjusting the pH value of the solution to be=5, adding the nano composite material of the invention to the solution, oscillating 6 h in a constant-temperature water bath oscillator at 25 ℃ and 250 rpm, sampling the solution at a preset time, and measuring the concentration of the acid scarlet (GR), carmine, congo red and methyl orange dye wastewater by spectrophotometry on the filtrate after filtering the 0.45 mu m microporous filter membrane after precipitation. The decolorization ratio of the nanocomposite of example 3 to acid scarlet (GR), carmine, congo red, methyl orange dye wastewater was 99.66%, 99.95%, 93.94%, 94.70%, respectively.
Because the natural attapulgite powder presents white color, the color of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared by the invention is obviously changed compared with that of the attapulgite powder, and the color of the obtained nanocomposite is black. FIGS. 1 (a) and (b) are SEM photographs of attapulgite and an attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared according to the present invention, respectively. As can be seen from the electron microscope photograph (a), the natural attapulgite has a nano rod-shaped structure, and the surface is smooth and free of any load. As can be seen from the electron micrograph (b), manganese dioxide particles and ferroferric oxide particles are attached to the surface of the attapulgite. The ferroferric oxide can solve the defect that the attapulgite in a heterogeneous system is difficult to recycle, and improves the effect of catalyzing and degrading organic pollutants. The attapulgite is used as a carrier of the nanocomposite material, so that the dispersibility of the manganese dioxide is improved, the agglomeration of manganese dioxide particles is prevented, and the stability of the whole structure is maintained.
The catalytic degradation performance and the recycling performance of the attapulgite/manganese dioxide/ferroferric oxide composite material on organic pollutants such as dye, phenol and the like are respectively tested.
1. Catalytic decolorizing property for dye wastewater
FIG. 2 is a graph showing the decolorization efficiency of an attapulgite/manganese dioxide/ferroferric oxide nanocomposite (example 1) prepared according to the present invention on acid scarlet (GR), carmine, congo red, methyl orange dye wastewater. As can be seen from FIG. 2, the material equilibrates the degradation of 3 dye waste waters of acid scarlet (GR), carmine, methyl orange at 4 h and the Congo dye waste water at 6 h. The decolorization rate of the nanocomposite to acid scarlet (GR), carmine, congo red and methyl orange dye wastewater can reach 100%, 99.67%, 92.99% and 95.45% respectively. The result shows that the prepared attapulgite/manganese dioxide/ferroferric oxide composite material can realize high-efficiency decolorization of the dye.
In the prior art, huang et al (2020) prepared nanorod alpha-MnO by hydrothermal method 2 Loading palygorskite and activating PMS to degrade rhodamine B. The results show that under the optimal conditions (catalyst dosage 0.10 g/L, PMS=0.10 g/L, pH (5.5.+ -. 0.1), temperature 20 ℃) 20 mg/L rhodamine B is almost completely degraded within 180 minutes. Liu Yanxia et al (2020) employ magnetic CuFe 2 O 4 Palygorskite (CuFe) 2 O 4 Activating PMS to degrade rhodamine B, under the optimal reaction condition (initial concentration of rhodamine B solution is 10 mg/L, PMS concentration is 0.1 g/L, initial pH value is 3, cuFe) 2 O 4 The addition amount of Pal is 0.3 g/L, and the rhodamine B degradation efficiency is 99.99% after 120 minutes of reaction. Li Yancheng et al (2021) prepared MnO by a two-step hydrothermal method 2 /CoFe 2 O 4 The magnetic composite catalyst shows that in MnO 2 /CoFe 2 O 4 The adding amount of the composite material is 0.3 g/L, the PMS concentration is 1.25 mmol/L, and the decolorization rate of the acid scarlet 3R solution with the initial concentration of 50 mg/L is 93.5% after the reaction is carried out for 10 min under the condition of pH value of 3. Compared with the materials, the composite material prepared by the invention has the advantages of wide pH application range, good decoloring effect and the like.
2. Degradation Properties of p-phenol
10 mg/L of phenol solution 60 mL was selected, 1 mL concentration of PMS solution 40 mmol/L was added thereto, pH=5 was adjusted, then 0.05 g of the nanocomposite of the present invention was added, 5 h was oscillated in a constant temperature water bath shaker at 25℃and 250 rpm, sampling was performed at a predetermined time, and the phenol concentration was spectrophotometrically determined on the filtrate after filtration through a 0.45 μm microporous filter after precipitation. FIG. 3 is a graph showing the degradation efficiency of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite (example 1) prepared according to the present invention with respect to phenol. As can be seen from fig. 3, the nanocomposite catalyzes PMS to degrade phenol, reaches equilibrium at 2 h, and the degradation efficiency can reach 97.89%. The result shows that the prepared attapulgite/manganese dioxide/ferroferric oxide nanocomposite can be used as a PMS catalyst to realize efficient removal of phenol.
3. Nanocomposite recycling performance
Taking acid scarlet (GR) dye wastewater with the concentration of 50 mL of 200 mg/L, adding PMS solution with the concentration of 2 mL of 30 mmol/L, adjusting the pH to be=5, adding the nanocomposite material, oscillating 6 h in a constant-temperature water bath oscillator at 25 ℃ and 250 rpm, filtering by a 0.45 mu m microporous filter membrane after precipitation, and measuring the concentration of the acid scarlet (GR) dye wastewater by a spectrophotometry. After magnetic separation (collecting the attapulgite/manganese dioxide/ferroferric oxide nanocomposite, washing and drying), the composite is used for catalytic degradation of acid scarlet (GR) dye wastewater again. FIG. 4 shows the cyclic decolorization efficiency of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite prepared according to the present invention (example 1) on acid scarlet (GR) dye wastewater. As can be seen from fig. 4, the decolorization rate of the nanocomposite after 5 times of catalytic degradation of acid scarlet (GR) dye wastewater was 90.74%. The result shows that the attapulgite/manganese dioxide/ferroferric oxide nanocomposite obtained by the invention has good recycling performance.
Pan Liang et al (2020) prepared Fe 3 O 4 the/RGO magnetic composite material is used as a catalyst for degrading methyl orange, and the methyl orange removal efficiency of 70.2% is obtained after 5 times of circulation of the catalyst. Shi Zhou et al (2017) successfully prepared a magnetic ternary material CoFeNi-LDH by a chemical coprecipitation method, and activated PMS to degrade azo dye congo red. After 3 times of cyclic regeneration, the decolorization rate of Congo red is 88%. Compared with the materials, the invention has good reusability and is easy to recycle.
The above description is only of the preferred embodiments of the present invention, and should not be taken as limiting the technical scope of the present invention, but all changes and modifications that come within the scope of the invention as defined by the claims and the specification are to be embraced by the invention.
Claims (7)
1. An application of an attapulgite/manganese dioxide/ferroferric oxide nanocomposite in degrading organic pollutants is characterized in that: the preparation method of the attapulgite/manganese dioxide/ferroferric oxide nanocomposite comprises the following steps: (1) Weighing a certain amount of ferrous sulfate heptahydrate, dissolving the ferrous sulfate heptahydrate in water, adding polyvinylpyrrolidone, stirring and heating, adding a sodium hydroxide solution with the concentration of 3-5 mol/L into the solution, continuously heating and stirring after the solution generates blue-green precipitate, stopping heating and cooling to room temperature after the blue-green precipitate turns black, centrifuging, washing and drying to obtain ferroferric oxide powder; (2) Taking attapulgite as a raw material, adding potassium permanganate, a divalent manganese ion reducing agent and the ferroferric oxide powder obtained in the step (1), adding pure water, oscillating in a water bath oscillator, carrying out ultrasonic treatment, centrifuging, washing, drying, and grinding to more than 200 meshes to obtain an attapulgite/manganese dioxide/ferroferric oxide nanocomposite; wherein: the dosage of the potassium permanganate is 40-60% of the mass of the attapulgite, and the mass ratio of the ferroferric oxide powder to the attapulgite is 1:3.3 to 1:5.
2. the use according to claim 1, characterized in that: in the step (1), the heating temperature is 70-80 ℃, and the continuous heating and stirring time is 1.5-2 h.
3. The use according to claim 1, characterized in that: in the step (2), the concentration of the divalent manganese ion reducing agent is 0.0319-0.0390 mol/L.
4. The use according to claim 1, characterized in that: in step (2), the conditions of water bath and drying are: oscillating 5-6 h in a water bath oscillator at 20-25 ℃ and 200-250 rpm, carrying out ultrasonic treatment, centrifuging, cleaning, and drying at 50-60 ℃ in an oven for 12-24 h.
5. The use according to claim 1, characterized in that: in the step (2), the attapulgite is attapulgite powder with the particle size of 200-320 meshes.
6. The use according to claim 1, characterized in that: in the step (2), the divalent manganese ion reducing agent is manganese sulfate or manganese chloride.
7. The use according to claim 1, characterized in that: the attapulgite has a nano rod-shaped structure, and ferroferric oxide nano particles and manganese dioxide particles are attached to the surface of the attapulgite.
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